Contents: Jos. Leidy, M.D., On a Mite in the Ear of the Ox; Thos. Meehan, On the Effects of Girdling Trees; Edw. D. Cope, On Megaptera bellicosa; Edw. D. Cope. On Holops pneumaticus; Edw. D. Cope, List of the Reptilia of the Eocene Formation of New Jersey; Jos. Leidy, M.D., Notice of Corundum; Jos. Leidy, M.D., Remarks on Fossils from Wyoming; Edw. D. Cope, Synopsis of the Species of the Chelydrinae; Edw. D. Cope, On an extinct Whale from California; Dr. O. Finsch, Remarks on the “Synopsis of the Genus Chettusia (Lovivanellus), with a description of a new species by J.A. Ogden”; Thos. Meehan, On the Numerical Order in the Branching of some Coniferae; Jos. Leidy, M.D., Remarks on some extinct Mammals; Edw. D. Cope, On Bathmodon radians; Jos. Leidy, M.D., Remarks on some extinct Vertebrates; Edw. D. cope, Curious Habit of a Snake; Edw. D. Cope, On Intelligence in Monkeys; Prof. P. Frazer, Jr., On a Sediment in Water from Geyser Springs, Saratoga; H. Allen, M.D., On the Appendicular Skeleton of Vertebrates; E.L. Berthoud, On Prehistoric Human Art from Wyoming and Colorado; T.A. Conrad, Descriptions and Illustrations of Genera of shells; Elliott Coues, Studies of the Tyrannidae, Part I. Revision of the Species of Myiarchus; Geo. W. Tryon, Jr., Catalogue and Synonymy of the Recent Species of the Family Lucinidae; Jas. Lewis, M.D., Shells of Herkimer and adjacent counties in the State of New York; Jas. Lewis, M.D., Shells of Tennessee (No. 2); Geo. W. Tryon, Jr., Catalogue of the Family Chamidae; Geo. W. Tryon, Jr., Catalogue of the Family Chametrachaeidae; Standing Committees for 1872. Illus.